Chairs may include different bases to support a seated user in different seated positioned. U.S. Pat. Nos. D176,813, D361,674, U.S. Pat. Nos. 3,272,555, 4,380,352, 4,536,031, 4,533,177, 4,869,552, 5,039,163, 5,154,438, 5,601,337, 5,683,139, 5,904,397 5,909,923, 5,944,382, 6,386,634, 6,669,292, 6,767,066, 6,817,667, 6,869,142, 6,910,736, 6,913,315, and 7,273,253, U.S. Patent Application Publication Nos. US 2007/0000111, 2005/0093354, 2005/0052061 and 2004/0189073 and World Intellectual Property Publication No. WO 2008/041868 disclose chairs that utilize different types of chair bases.
Many chairs include a chair base that supports movement of the seat or back of the chair to a reclined position. In some chairs, only a chair back will recline and the seat will stay substantially horizontal. In other designs, both the seat and back may move synchronously. Often, such chair bases utilize complex designs that include torsion springs, leaf springs or coil springs for supporting or controlling such recline movement. Such designs are often relatively expensive to manufacture.
A new chair base configuration is desired that can permit a relatively low cost chair base to provide a comfortable recline action of the seat or the back of a chair. Preferably, the new chair base provides a simple design that permits low cost manufacturing of the chair.